Welt insole and sewing rib for attachment thereto



Nov. 13, 1945. w. c. WRIGHT 2,389,114

WELT INSOLE AND SEWING RIB FOR ATTACHMENT THERETO Original Filed June 21, 1-941 2 Shee cs-Sheet 1 A A A A A A V A A A A A A A A AAAAAA A A A A A 1945- w. c. WRIGHT ,389,114

WELT INSOLE AND SEWING RIB FOR ATTACHMENT THERETQ Original Filed June 21, 1941 I '2 Sheets-Sheet 2 Patented Nov. 13, 1945 WELT 1N SOLE AND SEWING RIB FOR ATTACHIHENT THERETO Wallace c. Wright, Brookiield, N. Wright-Batchelder Corporation,

11., 'assignor to Boston, Mass.,

a corporation of Massachusetts Original application Jun 1944, Serial No. 533,818

4Clairns. (Cl. 36-22) My present invention is a novel and improved welt insole, and includes as a novel article of manufacture a sewing rib of synthetic plastic material, having a textile reinforcing base for attachment of the rib and insole blank together, this application being a divisional of my prior and copending application Ser. No. 399,049, filed June 21, 1941. Said prior application has now matured into Patent No. 2,348,583, covering the .method of manufacturing same.

As explained in my said parent application. I have discovered that a synthetic plastic material, such for example as the thermo-plastic vinyl resins or the like having the characteristics of Koroseal, Vinylite, or the like, can be made sufilciently tough, stitch-retaining, and of permanent pliability to be suitable for use in the manufacture of welt insoles, and particularly in a sewing rib for such insoles.

Heretofore it has been extremely diflicult to unite a plastic with sufiicient strength and adherence on an insole blank of leather or other material to enable the sewing rib to stand up during the lasting, inseaming, trimming and other operations to which such insole and rib are subjected during the usual manufacture of welt footwear.

I have discovered that by using a layer of adhesive on which the synthetic plastic can be aplied, preferably during the molding or extruding operation, that an extremely strong bonding is afforded by the uniting of the textile layer portion of the sewing rib on to the insole blank by the use of standard types of adhesives.

Preferably, also, I may apply a preliminary thin surface coating of the synthetic plastic to a sheet or strip of textile material and, thereupon, apply the upstanding portion of the sewing rib, preferably, with a sufiicient mass of base material to form a firm union with the preliminary coating already applied to the textile material.

In carrying out my invention, I can either apply an entire sheet of the thermoplastic from which the sewing rib is to be formed onto the sheet of textile material; then cutting the same into strips, and thereafter applying the upstanding portion of the rib, as will be hereinafter explained in detail. Or I may coat the strips of textile independently and draw the same thru an extruding die, which die at the same time applies the sewing rib in pre-formed cross-section upon said strip while the plastic material is in molten condition.

Thus I provide a reinforced synthetic plastic e 21, 1941, Serial No. Divided and this application of vinyl resin or other composition, having stitchretaining and permanent pliability typical of the characteristics of Koroseal, Vinylite, or the like.

Referring to the drawings:

Fig. 1 is a diagrammatic view of a sheet of textile material, having a preliminary coating of synthetic material suitable for the subsequent rib and coating attachment on the coated side; while the textile layer is preferable for uniting to the insole by adhesive;

Fig. 2 illustrates a strip cut from the sheet shown in Fig. 1; in both these figures the thickness of the textile layer and coating are overdrawn for clarity; v

Fig. 3 is a view in perspective of a fragmentary portion of the strip after the pair of sewing ribs have been added, this being shown on an enlarged scale;

Fig. 4 is a plan view showing the zig-zag cut separating the two ribbed portions into each individual sewing rib for attachment to an insole: Fig. 5 is a plan view illustrating the process of cementing and attaching the prepared rib to an insole;

Fig. 6 is an enlarged fragmentary view in cross-section showing the margin of an insole with my improved sewing rib and a reinforcing st ip;

Fig. '7 is a view corresponding to Fig. 6 without any reinforcing, and 4 Fig. 8 is a fragmentary cross-sectional view illustrating a shoe structure and also a reinforcing or gemmed duck layer where same is desired. In my developments and improvements in the boot and shoe art utilizing synthetic plastic material, it has been found extremely difficult'to utilize a suitably strong synthetic plastic which could be cemented to an insole blank of leather or other suitable material. I have, therefore, in my present invention discovered that by providing a thin textile layer on which the synthetic plastic material was built up or applied, I was then enabled to secure such a flexible synthetic rib structure to an insole blank by a simple cementing operation, as the textile layer and cement would adhere properly to the insole blank on the textile surface, and the synthetic coated layer would present an affinity for the plastic rib or structure on the synthetic coated surface.

As shown in Fig. 1, therefore, I have illustrated diagrammatically a-sheet of textile material, I, to which a thin coating 2 of synthetic plastic, either of the same material as that from which the sewing rib is to be constructed, or a sufficienth similar synthetic material, to merge with the rib plastic when a strip cut from the sheet is drawn thru a die, which die applies the plastic material to the plastic coated surface 2. The thickness of both the textile material I and the preliminary coating 2 is greatly overdrawn in the attached drawings, as previously noted.

With the coated sheet I as illustrated. I then cut the same along suitable lines 3-3 into strips, such as ilustrated in Fig. 2, this strip being equal in width for two subsequent rib structures to be cut therefrom.

.'',ith the strip thus prepared, I then draw the same thru a suitable die which applies a second coating 5 of plastic, which will merge with the coating 2 into a homogeneous mass for the length and width of the strip, and also simultaneously form a pair of sewing ribs 66 adjacent each side of the edge of the strip, thus providing an outer marginal surface of the base of each rib 6, and a relatively thickened intermediate portion 8 between the ribs 6-6. Thereupon, I subject the strip thus prepared to a zig-zag cutting operation, designated as 9, in Fig. 4, thus forming two ribbed structures with homogeneous bases or flanges, said flanges particularly from the inner portion 8 being of sufllcient width to afford a strong union between the flanged rib strips and the insole to which the same are to be attached.

Such pinked or V-shaped flange structure is designated generally at Ill and, if desired, the outer flange I may also be pinked, as illustrated at I2. Thus the pinked flange portions of i0 and I! of each separated strip, together with the sewing rib 6, may be quickly and expeditiously applied around the marginal edge of an insole blank l5, irrespective of the contour, while maintaining the pinked flange portions 10, and whether or not the outer flange l is also pinked evenly and smoothly around the insole, particularly at the toe, as best shown in Fig. 5.

Furthermore, the strip or rib and flanged synthetic material as thus prepared, with the textile face I on the lower or bottom portion, has a capacity for being applied around curves at any part of its length and does not require any separate hand-pinking or the like, as is often necessary in laying a flat piece of leather at curves.

In my improved structure, it is thus prepared ready for attachment both to straight and convex soles, concave curves, and the flanged portions will be maintained flat while the perpendicularly extending rib portions will, of course, follow such a curve without difficulty.

Furthermore, by having this rib structure of synthetic plastic material, which is permanently flex ble for the life of the shoe, the laying of same .on an insole blank I5 is greatly facilitated.

With the insole structure thus completed and as indicated in Fig. 7, it can then be utilized in welt shoe manufacture entirely independently of Gemming or reinforcing, although either may be employed if desired.

As shown in Fig. 6, I have illustrated a reinforcing strip 20 as a narrow gemming layer; and in Fig. 8 I have illustrated a typical gemmed duck layer 2| the insole IS with its attached plastic sewing rib in a completed shoe structure wherein is incorporated in the shoe uniting the upper materials 23 and 24 by inseam stitching 25 to a welt 26, and the latter by the outsole stitching 28 to the outsole 30, the shoe also being completed by the filling 33 and, where desired, the sewing rib with the edge portion of the upper is trimmed during the upper trimming, as indicated at 35.

My invention of an inherently and permanently flexible sewing rib suitable for manufacture as a distinct article in the shoe trade, and preferably pre-pinked to facilitate the application to any part of the rib around the toe of an insole is, I believe, a distinct novelty and greatly benefits the complete shoe structure and also renders the same permanently flexible.

Such a flexible rib is, preferably, formed of synthetic plastic material or the like permanently flexible material which is stitch-retaining and, preferably, suitable to be secured to an insole blank by stitching or adhesive.

Also, I may form my novel type of rib with the stitch-retaining rib portion and the lower attaching flange portion mounted on a strip of canvas or the like, with the latter of greater width than the flange portion.

I claim:

1. A welt insole of the kind described, comprising an insole blank of suitable thickness, contour, and material, together with a sewing rib of stitchretaining, permanently pliable, synthetic plastic material, and a strip of textile material interposed between the sewing rib and the insole blank, said textile material being inherently united with the synthetic plastic material, and adh'esively united with the insole blank along the marginal portion of said blank.

2. As a new article of manufacture, a strip of stitch-retaining, permanently pliable, synthetic plastic material prepared for attachment to an insole blank by securing said material at the base of the rib to one side-of a strip of textile material, the opposite surface of the textile material being suitable for adhesive attachment to the insole blank of different material.

3. As a new article of manufacture, a strip of stitch-retaining, permanently pliable, synthetic plastic material prepared for attachment to an insole blank by securing said material at the base of the rib to one side of a strip of textile material, the opposite surface of the textile material being suitable for adhesive. attachment to the insole blank of different material, said synthetic plastic constituting an upstanding stitch-retaining portion, and a horizontal strip-attaching portion.

4. As a new article of manufacture, a strip oi! stitch-retaining, permanently pliable, synthetic plastic material prepared for attachment to an insole blank by securing said material at the base of the rib to one side of a stri of textile material, the opposite surface of the textile material being suitable for adhesive attachment to the insole blank of different material, said synthetic plastic constituting an upstanding stitch-retaining portion, and a horizontal strip-attaching portion, said horizontal strip being pre-pinked.

WALLACE C. WRIGHT. 

